(D-Ser-(Bu(sup t))(sup 6)-des-gly)-LHRH ethylamide (D-Ser-(Bu(sup t))(sup 6)-des-gly)-luteinizing hormone-releasing hormone ethylamide Luteinizing hormone-releasing hormone, (D-ser-(Bu(sup t))(sup 6)-des-gly)-, ethylamide OK6702000